Question

I can get the code of a stored procedure using the syscomments table.

select so.name, sc.text as storedproccode
from sysobjects so (nolock)
inner join syscomments sc (nolock) on sc.id = so.id
where so.name = 'tablename'

How can I get the code for a specific foreign key constraint? I have the foreign key name.

Let me clarify what I’m looking for.

I find my table in the Object Explorer and expand the list of keys. If there is a primary key I can then right click on the primary key constraint and bring up the script in a new window.

The code looks like this:

USE [Gemini]
GO
/****** Object:  Index [PK_CM_FULFILLMENT_HISTORY]    Script Date: 02/17/2012 16:50:23 ******/
ALTER TABLE [dbo].[CM_FULFILLMENT_HISTORY] ADD  CONSTRAINT [PK_CM_FULFILLMENT_HISTORY] PRIMARY KEY NONCLUSTERED 
(
    [pan] ASC,
    [RequestCode] ASC,
    [RequestDate] ASC
)WITH (SORT_IN_TEMPDB = OFF, IGNORE_DUP_KEY = OFF, ONLINE = OFF) ON [GEMINI_12_Indx_FG]

I can also do this with foreign key constraints.

Is there any way to retrive the code (script) of these constraints?

Thanks

Answer 1

I found a script that does the trick.

Declare        @dbname varchar(128)
            ,  @tablename varchar(128)
            ,  @query nvarchar(4000)


select   @dbname = 'gemini'
       , @tablename = 'cm_fulfillment_house'


SET @QUERY = 
'USE ' + @DBNAME + '


SELECT CAST(F.NAME AS VARCHAR(255)) AS ForeignKeyName,
CAST(c.name as varchar(255)) AS ForeignTable,
CAST(fc.name as varchar(255)) AS ForeignColumn,
cast(fc2.name as varchar(255)) as ForeignColumn2,
CAST(p.name as varchar(255)) AS PrimaryTable,
CAST(rc.name as varchar(255)) AS PrimaryColumn,
cast(rc2.name as varchar(255)) as PrimaryColumn2
INTO #GetFKConstraints 
FROM SYSOBJECTS F 
INNER JOIN SYSOBJECTS C ON F.PARENT_OBJ = C.ID
INNER JOIN SYSREFERENCES R on F.ID = R.CONSTID 
INNER JOIN SYSOBJECTS P ON R.RKEYID = P.ID
INNER JOIN SYSCOLUMNS RC ON R.RKEYID = RC.ID AND R.RKEY1 = RC.COLID
INNER JOIN SYSCOLUMNS FC ON R.FKEYID = FC.ID AND R.FKEY1 = FC.COLID
left join syscolumns rc2 on r.rkeyid = rc2.id and r.rkey2 = rc.colid
left join syscolumns fc2 on r.fkeyid = fc2.id and r.fkey2 = fc.colid
WHERE F.TYPE = '+'''F'''+''

select @query = @query + ' and c.name = ''' + @tablename + ''''

+ '

--SELECT * from #GetFKConstraints'+'

SELECT ' + '''ALTER TABLE ''' + '+ ForeignTable + ' + ''' 
DROP CONSTRAINT ''' + '+ ForeignKeyName 
FROM #GetFKConstraints 
ORDER BY ForeignTable'
+'

SELECT ' + '''ALTER TABLE ''' + '+ ForeignTable +' + ''' 
ADD CONSTRAINT ''' + '+ ForeignKeyName +' 
+ ''' FOREIGN KEY ('''+ ' + ForeignColumn + '+ ''') 
REFERENCES ''' + '+ PrimaryTable + ' + '''(''' + '+ PrimaryColumn + '+ ''')''' +
'FROM #GetFKConstraints 
ORDER BY ForeignTable
'
select @query

EXEC (@QUERY)
GO